Mesoporous silica nanoparticles for active corrosion protection

Area of Science:

• Materials Science
• Nanotechnology
• Corrosion Science

Background:

• Aluminum alloys are susceptible to corrosion, necessitating advanced protective coatings.
• Traditional passive coatings often lack self-healing capabilities, limiting long-term performance.
• Nanocontainers offer a promising approach for delivering corrosion inhibitors effectively.

Purpose of the Study:

• To synthesize monodisperse, mesoporous silica nanoparticles for use as nanocontainers.
• To load these nanoparticles with 1H-benzotriazole (BTA) and embed them in a SiOx/ZrOx sol-gel coating.
• To evaluate the corrosion protection performance of the developed active coating on aluminum alloy AA2024.

Main Methods:

• Synthesis of monodisperse, mesoporous silica nanoparticles with high surface area and controlled pore size.
• Loading of BTA into the silica nanocontainers.
• Fabrication of hybrid SiOx/ZrOx sol-gel coatings incorporating BTA-loaded nanoparticles.
• Evaluation of corrosion resistance using Scanning Vibrating Electrode Technique (SVET) in 0.1 M NaCl solution.

Main Results:

• The silica nanoparticles exhibited high surface area (~1000 m2·g⁻¹), narrow pore size distribution (~3 nm), and large pore volume (~1 mL·g⁻¹).
• Successful loading and homogeneous distribution of BTA-loaded nanoparticles within the SiOx/ZrOx coating were achieved.
• The active coating significantly improved the wet corrosion resistance of AA2024 compared to the passive coating.
• Controlled, pH-dependent release of BTA was observed, suggesting a corrosion-triggered release mechanism.

Conclusions:

• Monodisperse, mesoporous silica nanoparticles effectively serve as nanocontainers for BTA.
• Embedding BTA-loaded nanoparticles into SiOx/ZrOx coatings enhances aluminum alloy corrosion protection.
• The system demonstrates potential for self-healing due to corrosion-triggered inhibitor release.